Obese women are more likely to gain more weight during pregnancy making it harder to drop the pounds after delivery.

A study by researchers at Kaiser Permanente looked at the medical records of nearly 1,700 obese women. They found nearly 75% gained more than the recommended 15 pounds during pregnancy for their weight class. A year after delivery, most had only lost 60% of the weight they gained, so if a woman gained 30 pounds during pregnancy, she still had 12 of those pounds one year later.